This could be a borderline advertisement, not to mention subjective, but the question is an honest one. For the last two months, I\'ve been developing a new open source profiler
There is EQATEC Profiler that's a free .Net profiler that I have been meaning to use.
One thing I would like to see is Mono compatibility. I have started dabbling in Mono, and it would be great to have a .Net and Mono profiler!